Understanding Precedence

Macros often contain mathematical formulas. Those formulas can sometimes become quite complex. Any time a formula contains more than one operator (such as + or -), VBA needs to figure out in which order to perform the operations. This is where the concept of precedence comes into play. Precedence is the built-in macro logic that determines the order in which the operations occur. This is the normal order:

Notice that there are two entries in the precedence list in which there are two operators. Multiplication and division are at the same precedence level, as are addition and subtraction. If a formula involves two or more operators at the same precedence level, then the operators are evaluated from left to right within the formula.

If you want to change the order in which a formula is evaluated, you need to use parentheses. Operations within parentheses are evaluated before those outside of them. Thus, a formula such as 3 * (4 + 2) would produce a result of 18 because the addition within the parentheses takes precedence over the multiplication outside the parentheses. If the parentheses had been omitted, then 3 * 4 + 2 would have resulted in 14.